668 research outputs found
Lipkin translational-symmetry restoration in the mean-field and energy-density-functional methods
Based on the 1960 idea of Lipkin, the minimization of energy of a
symmetry-restored mean-field state is equivalent to the minimization of a
corrected energy of a symmetry-broken state with the Peierls-Yoccoz mass. It is
interesting to note that the "unphysical" Peierls-Yoccoz mass, and not the true
mass, appears in the Lipkin projected energy. The Peierls-Yoccoz mass can be
easily calculated from the energy and overlap kernels, which allows for a
systematic, albeit approximate, restoration of translational symmetry within
the energy-density formalism. Analogous methods can also be implemented for all
other broken symmetries.Comment: 15 LaTeX pages, 8 eps figures, submitted to Journal of Physics
Solution of the Skyrme-Hartree-Fock-Bogolyubov equations in the Cartesian deformed harmonic-oscillator basis. (VII) HFODD (v2.49t): a new version of the program
We describe the new version (v2.49t) of the code HFODD which solves the
nuclear Skyrme Hartree-Fock (HF) or Skyrme Hartree-Fock-Bogolyubov (HFB)
problem by using the Cartesian deformed harmonic-oscillator basis. In the new
version, we have implemented the following physics features: (i) the isospin
mixing and projection, (ii) the finite temperature formalism for the HFB and
HF+BCS methods, (iii) the Lipkin translational energy correction method, (iv)
the calculation of the shell correction. A number of specific numerical methods
have also been implemented in order to deal with large-scale multi-constraint
calculations and hardware limitations: (i) the two-basis method for the HFB
method, (ii) the Augmented Lagrangian Method (ALM) for multi-constraint
calculations, (iii) the linear constraint method based on the approximation of
the RPA matrix for multi-constraint calculations, (iv) an interface with the
axial and parity-conserving Skyrme-HFB code HFBTHO, (v) the mixing of the HF or
HFB matrix elements instead of the HF fields. Special care has been paid to
using the code on massively parallel leadership class computers. For this
purpose, the following features are now available with this version: (i) the
Message Passing Interface (MPI) framework, (ii) scalable input data routines,
(iii) multi-threading via OpenMP pragmas, (iv) parallel diagonalization of the
HFB matrix in the simplex breaking case using the ScaLAPACK library. Finally,
several little significant errors of the previous published version were
corrected.Comment: Accepted for publication to Computer Physics Communications. Program
files re-submitted to Comp. Phys. Comm. Program Library after correction of
several minor bug
An HFB scheme in natural orbitals
We present a formulation of the Hartree-Fock-Bogoliubov (HFB) equations which
solves the problem directly in the basis of natural orbitals. This provides a
very efficient scheme which is particularly suited for large scale calculations
on coordinate-space grids.Comment: 5 pages RevTeX, (Postscript-file also available at
http://www.th.physik.uni-frankfurt.de/~bender/nucl_struct_publications.html
or at ftp://th.physik.uni-frankfurt.de/pub/bender ), accepted for publication
in Z. Phys.
Skyrme-HFB deformed nuclear mass table
The Skyrme-Hartree-Fock-Bogoliubov code HFBTHO using the axial (2D)
Transformed Harmonic Oscillator basis is tested against the HFODD (3D Cartesian
HO basis) and HFBRAD (radial coordinate) codes. Results of large-scale
ground-state calculations are presented for the SLy4 and SkP interactions.Comment: 6 LaTeX pages, 3 figures, uses aipproc, presented at International
Conference NUCLEAR PHYSICS, LARGE and SMALL, Hotel Hacienda Cocoyoc, April
19-22, 2004, to be published in AIP Proceedings, see also
http://www.fuw.edu.pl/~dobaczew/thodri/thodri.htm
Nuclear ground-state properties from mean-field calculations
The volume and surface effects in the nuclear local energy density and the
volume and surface components of the pairing interaction are discussed in the
context of the mean-field, Hartree-Fock-Bogoliubov description of atomic
nuclei. Predictions of properties of exotic nuclei close to the particle drip
lines are presented.Comment: Presented at the 3rd International Conference on Exotic Nuclei and
Atomic Masses, Hameenlinna, Finland, July 2-7, 2001, to be published in
European Physical Journa
Pairing anti-halo effect
We discuss pairing correlations in weakly bound neutron rich nuclei, by using
the coordinate-space Hartree-Fock-Bogolyubov approach which allows to take
properly into account the coupling to particle continuum. We show that the
additional pairing binding energy acts against a development of an infinite rms
radius, even in situations when an l=0 single-particle orbital becomes unbound.Comment: 10 RevTeX pages, 3 EPS figure
Variation after Particle-Number Projection for the HFB Method with the Skyrme Energy Density Functional
Variation after particle-number restoration is incorporated for the first
time into the Hartree-Fock-Bogoliubov framework employing the Skyrme energy
density functional with zero-range pairing. The resulting projected HFB
equations can be expressed in terms of the local gauge-angle-dependent
densities. Results of projected calculations are compared with those obtained
within the Lipkin-Nogami method in the standard version and with the
Lipkin-Nogami method followed by exact particle-number projection.Comment: 11 pages, 6 figure
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